Title text: You could at least not wear the lab coat everywhere, dude.

Explanation

Bill Nye is a scientist well known in the United States for his science-focused television show targeted to elementary school children (website).

A family is sitting at a table in a restaurant, and the mother asks her children a science-related question about the ice-cubes in their drinks. She is hoping to prompt Bill Nye, sitting at the next table, to join the conversation and perhaps inspire her kids. Thinking he has not heard, the mother then coughs slightly and starts to repeat the question. His then immediate and abrupt dismissal of her is antithetical to his television persona, where he is consistently enthusiastic about science and keen to take any opportunity to teach the viewer.

The use of the word "tribulation" implies that being recognized and accosted in public is a cause of much suffering and misery to Mr Nye.

The title text contains another joke. He eats a meal in public where he does not want to be recognized or harassed with questions, however, he wears a lab coat. Regardless of Bill Nye's otherwise iconic and recognizable appearance, wearing a lab coat in public will probably draw the gazes and curiosity of others, no matter who is wearing it.

Ice pops and cracks when dropped in a glass of water because of thermal expansion: the much warmer water causes the surface of the ice to expand, resulting in audible internal fractures in the brittle structure.

Transcript

THE TRIBULATIONS of BILL NYE

[A restaurant. A mother and two children sit at one table; Bill Nye sits at another.]

Mother: Hey, kids, see how the ice cracks and pops in your water? I wonder what causes that... *Ahem* I said, I wonder what--

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